Acetylene generator



April 17, i 1934.

L. CAMPBELL, `.IR

ACETYLENE GENERATOR Filed Aug. 19, 1950 2 Sheets-Sheet l m n m l wie L. CAMPBELL, JR

ACETYLENE GENERATOR Allr'il 17, 19:54.

2 sheets-sheet 2 Filed Aug. 19

Patented Apr. 17, 1934 PATENT OFFICE ACETYLENE GENERATOR Lorn Campbell, Jr., Lakewood, Ohio Application August 19,

Claims.

This invention relates to acetylene generators, and more particularly to generators of the low pressure flash-generation type, wherein charges of carbide are fed from a hopper into the water 5 withinV the generator, the supply of carbide being automatically controlled by a valve which closes the discharge opening of the hopper when the pressure of the generated gas reaches a predetermined amount.

In the art of generating acetylene gas from calcium carbide, three general types of generators are employed. First, there are those embodying the water-to-carbide method, wherein the water drops on the carbide. Next are those embodying what is known Aas the kiss or recession method. In generators coming under this classification, the carbide is suspended in a chamber where water is allowed to come up and contact with it, generating a gas pressure which forces the water away from the carbide. The third type is the carbide-to-water type, wherein the carbide is dropped into a body of water.

The principal objection to the type first de scribed is that an intense local heat is generated at the point where the water contacts with the carbide, which causes disintegration of the acetylene gas. It is well known that at 200 C., polymerlzation of acetylene takes place, three molecules of acetylene combining to form one molecule of benzene (CSHG) which requires a correspondingly greater quantity of oxygen for its combustion than is required by acetylene.

In the second type of generators, the carbide, being normally suspended in the presence of wa- F ter vapor, absorbs the moisture and is dissipated. Furthermore, in the operation of generators of this type, the Water contacting lwith the carbide heats the water at the point of contact and, while it istrue that the water moves, its movement is always in an up-and-down direction, so that the hot water always stays on top, thelcold water remaining on the bottom, and there is no -means presented for cooling the top layer of the hot 'water so that after continuous use the surface water becomes exceptionally hot and polymerization of the acetylene gas also takes place.

In the third type of generators, where the carbide is fed to the water, the carbide is generally dropped into a chamber of still water; all of the heat of generation causes the water to become heated, the hot water rising to the surface, where the carbide first contacts with it, causing a high temperature which tends to create the same disintegration of the acetylene gas as previously described.

I have been successful in overcoming the undesirable features just described by combining to a certain extent the last two types of generatorsfeeding relatively small-size carbide to water in such a manner as to pierce the water and overcome the surface tension thereof at all times. While using such feeding means, I simultaneously exclude or insulate the valve mechanism from the moist atmosphere of the generating chamber around the carbide feed valve. The carbide is dropped into water having a forced circulation which is not limited to simply an up movement and a down movement, but which in reality has four movements, namely: up, and down, horizontal", andA circular, thereby permitting the generation of pure, cool, acetylene gas at all times.

It is the general purpose and object of the invention to provide a generator which will be free from the objections pointed out hereinbefore; which will be safe, dependable, and eiiicient in operation; which is compact and portable; which will not only produce pure acetylene but will prevent the escape of such gas into the compartment or space in which the generator is located. A further obj ect of the invention is to provide a generator which is capable of employing small-sized carbide without the dangers and disadvantages which ordinarily attend the use of carbide of this small size. Further and more limited objects of the invention will appear hereinafter and will be realized in and through the construction and arrangement of parts shown in the accompanying drawings, wherein Fig. 1 represents a central sectional view through a generator constructed in accordance with my invention, the lower portion of the carbide hopper and the upper portion of the carbide delivery tube being shown in elevation; Fig. 2 a detail in section corresponding to the line 2-2 of Fig. 1; and Figs. 3 and 4 are sectional views 95 corresponding respectively to the lines 3-3 and 4 4 of Fig. 1 and looking in the direction of the arrows.

As stated hereinbefore, the generator is designed with special reference to the use of carbide in small particles, the purpose being to insure a quick or flash generation of acetylene, but without the disadvantages, which will be pointed out hereinafter, ordinarily attendant upon the use of carbide in this form. The form of generator shown in the drawings will now be described by reference characters.

1 denotes a cylindrical open-top tank or casing having within the lower portion thereof a frustoconical collar 2, the bottom of which is welded or otherwise suitably secured to the interior of the tank 1 by means of a vertical annular ange 3 depending from a frusto-conical seat 4 at the base of the collar 2. The collar 2 is provided with one or more outlet openings 5, located preferably immediately above the seat 4, two such outlets being shown, the said outlets being arranged diametrically opposite each other.

6 denotes a frusto-conical gas generating and collecting chamber, the lower portion of which surrounds and is spaced from the collar 2 and the lower end of which is provided with an annular bead 7 resting upon the seat 4 of said collar. The chamber is removably secured in place by means of a plurality of' rods 8, two of which are shown, located diametrically opposite each other and each being rotatably mounted in sleeves 9, 9a, secured to the inner wall of the tank 1 andlocated respectively adjacent the top of the tank and adjacent to and above the bead 7. Each rod is shown as provided with an operating handle 8a at its upper end and with a foot or projection 8b which, by rotating .the rod inthe appropriate direction, will enter one of the ports 10 in the lower portion of the chamber 6 above the top of the bead 7, thereby to locate the said ports and retain the chamber 6 in place. The ports 10 are angularly spaced a considerable distance from the ports 5, the purpose of which arrangement will be pointed out hereinafter. Two such ports 10 are shown in the drawings, and these ports are shown as arranged each approximately 90 from the ports 5. The upper end of the chamber 6 is provided with an outwardly extending annular ange 11, which is seated upon an annular horizontal shoulder 12a extending outwardly from the inner wall of the upper portion of a reinforcing collar 12, carried by and secured to the upper end of said chamber. The upper end of the collar 12 is provided with an inner cylindrical surface 12b extending upwardly from the shoulder 12a and forming with the ange 11 an annular seat for the upper end of an inverted frusto conical extension 13a of the carbide delivery-tube 13. The upper end of this frustoconical or hopper-like extensionof the carbide delivery tube is provided with an outwardly extending annular ange 13h which is seated in a gasket 14, preferably of soft rubber, which gasket ts within the seat in the top of the oo llar 12, resting on the flange 12E. It will be noted that the tube 13 extends downwardly within the chamber 6 to a comparatively short distance above the normal or inactive level of the water in the tank and chamber, such level being indicated at A A.

It will be noted further that the lower end of the tube is' provided with a frusto-conical skirt 13c which extends below the lower end of the tube proper. 15 denotes a carbide receptacle having a hopper bottom 15a, this bottom being provided adjacent its lower end with an annular angular rib 16, 16a, the portion 16e of which is adapted to rest on top of the gasket 14. The bottom of the hopper is provided with a central opening 17 for the discharge of carbide into the upper hopperlike extension of the tube 13. Cooperating with the opening 17 is an upwardly seating conical` valve 18 secured by a nut 18a on the bottom of a rod 19, the upper end of the rod being provided with a hook 19st received within a ring 20 which may be carried on the bottom of a rod 21, extending through a diaphragm 22 which is clamped to the top of the carbide chamber by a cover 23 having an upwardly projecting dome-shaped center 23a provided with a central opening 23D for the upper end of the rod 21. Pivoted to the upper end of the rod 21 is a lever 24, the short arm of which is provided with a cam extension 24a which, when the lever is swung to a vertical position, will raise the rod 21 and the diaphragm 22 and the rod 19, thereby to cause the valve 18 to close the opening 17. Surrounding the rod 21 within the dome 23a and bearing at its upper end against the cap portion of said dome is a helical spring 25, the lower end of which bears against a, central reinforcing plate 26 on top of the diaphragm 22. An inverted conical valve 18b is mounted to slide on the rod 19 between the top of the valve 18 and a stop 19b on said rod.

The carbide receptacle 15 is detachably connected to the top of the chamber 6 by means of a plurality of bolts 27 each having its upper end pivotally mounted between lugs 28 on the hopper 15a, the lower end of each bolt being received within a slot in a lug 29 carried by the collar 12 and the bolts being secured in place each by means of a wing nut 30. By setting up the nuts a tight joint is provided between the hopper of the carbide receptacle and the chamber 6.

Supported on a bracket 31 carried by the gas chamber 6 is a combined water seal and flashback check and drier. This apparatus comprises a cylindrical casing 32 the bottom of which is supported by the bracket and which is provided at a suitable distance above its bottom with an overflow opening 32a controlled by a plug 33. This overflow opening determines the depth of the water 33a in the seal. Above the overflow opening, a perforated disk 34 extends across the casing and forms the bottom of a receptacle for coke, indicated at 35, the top of the receptacle being formed by a circular disk or plate 36 having a seat 36a on the lower outer side thereof for the top of the casing 32 and a similar seat 36b at the top thereof for an upper extension 37 of the casing 32, the said upper extension having a top provided with a vent opening 37a.

Cast or otherwise formed with or connected to the plate or disk 36 is an elbow 38 which projects through the casing 32, 37 and which is connected by tubular members 39, 40 and a coupling 41 with the top of the chamber 6. 42 denotes a short vertical tube connected with the upper branch of the elbow Within the casing member 37, the upper end of the tube communicating with one end of a coupling 43 within such chamber member and having an inverted U-shaped passage 43a therein. A tube 44 is connected with the opposite end ofK the coupling member 43 and extends downwardly through the coke baile chamber and 'nearly to the bottom of the water seal. At one side of the tube 44 is a smaller tube 45 the upper end of which is located in the chamber provided within the casing member 37, above the plate 36 and the lower end of which extends into the water seal, being located between the bottom of the tube 44 and the top of the seal. At another side of the tube 44 is a lling tube for the water seal, the latter tube being indicated at 46 and having its upper end mounted in the plate 36, while its lower end extends nearly to the bottom of the casing 32, preferably to about the plane of the bottom of the tube 44. 'Ihe baie chamber 35P- is provided near its upper end witha valved connection 47 to which a hose may be connected for conducting the gas to a blowpipe or to burners for lighting and cooking purposes.

With the parts constructed and arranged as described, the apparatus will be operated in the folsecure the same in place.

lowing mannerz-The tank A will be filled with water to the level A-A. If not previously done, insert the conical chamber 6 in place turning the locking rods 8 so as to position the chamber and The carbide receptacle may then be lled by placing the same on its side, having rst moved the lever 24 to a vertical position to close the opening 17 by the valve 18. The filling plug 48 will be removed and the carbide inserted therethrough and, after the chamber is lled,the plug will be replaced. As pointed out hereinbefore, the generator is intended for use with carbide of a small size. Next remove the plug 33 and fill the water seal through the vent opening 37a until the water overflows through the opening 32a, at which time the plug should be replaced. The carbide receptacle is then placed on top of the chamber 6, in the manner shown in the drawings, being secured in place by the swinging bolts 27 and the nuts 30. The generator now being ready for operation, it may be started by moving the lever to the horizontal position shown in Fig. 1, which will open the valve 1`8 and allow carbide to be delivered through the opening 17 and the tube 13 into the water within the chamber 6. By using a tube 13 of small diameter and constructing and locating it in the manner shown and described, the ow of carbide is concentrated and, because of the length ofthe tube (due to the distance between the funnel or hopper-like portion 13a thereof and the water level in the receptacle 6), the carbide breaks through the surface of the water, overcoming the surface tension thereof, with the \result that there will be no floating island formation and the decomposition of the carbide, with` the evolution of acetylene, occurs within a large volume of water.

The generation of -acetylene by the action of water on carbide is an exothermic reaction; but,.

if this reaction occurs in the presence of a large volume of water, there will be no resultant high temperature anywhere, much less at any place where danger or injury to the apparatus, or to persons in the vicinity of such apparatus, might occur. By virtue of the use of carbide in a finely divided condition, the evolution of gas will be very rapid, in fact, practically instantaneous. In apparatus as constructed heretofore for the use of small-sized carbide, this rapid evolution of gas has produced a frothing action, the froth frequently extending as high as the point at which the carbide is discharged into the generator. This froth contains suilicient moisture to cause a decomposition of carbide thereby, with the evolution of heat which, owing to the absence of water in suliicient volume to absorb and reduce the temperature to a safe degree, has resulted in injury to the generators. Furthermore, where the froth is built up to and reaches the hopper feed, it obstructs the delivery of carbide from the hopper by the decomposition of the carbide at the delivery point and the consequent clogging of such delivery by such decomposed carbide. Still further, the presence of moisture in the gas chamber proper renders the gas impure. By concentrating the delivery of the carbide in the manner shown and described, this frothing effect is entirely obviated, as the carbide, even though in a finely divided condition, will break through the surface of the water, and the intense heat due to the decomposition of the carbide by the water will be disseminated through a suficiently large volume of water to prevent any injurious heat elfects, one of which is the production of It will be noted that the tube 13 is provided with the conical skirt 13c connected thereto above its lower end and extending below suchV end. This hood serves to prevent any water of condensation that may collect upon and flow down the outer surface of the tube from contacting with the carbide at the bottom of said tube. This prevents the tube from becoming gradually clogged at the delivery end thereof by the action of the water upon the carbide at this point.

As is well known, as soon as the pressure of the gas generated within chamber lreaches a point predetermined by the spring 25 and the throw of the valve 18, the latter valve will be closed by the pressure of gas beneath the diaphragm, and-there will be no further feed of the small-sized carbide until the pressure of the gas falls to an extent to enable the diaphragm to be depressed by the spring and the valve to be open. Because of the fact that it is contemplated that small-sized carbide shall be used, the generation of gas from the carbide dropped into the water is nearly instantaneous, and the carbide is fed into the water in successive charges. This rapid evolution of gas creates a considerable pressure upon the water within the chamber 6. As soon as the level of the water is depressed below the top of the collar 2, the major portion of the water within such chamber will be contained within and below the top of the collar rapid evolution of the gas, the water carrying the carbide in suspension will be discharged rst through the openings 5 and will then follow a circuitous path to the openings 10, before it ,can escape into the tank l. There will be a circulation of the hot carbide-containing water from inside thg collar 2 and partly around the annular space formed between said collar and the chamber 6, to and through the openings 10. Owing to the length of this circuitous course or passage, all of the carbide will have been decomposed before the sludge-laden water is delivered from the collar 2 and chamber 6 into the tank l; hence there can be no discharge of acetylene through such exterior tank, even under conditions of y,maximum acetylene pressure within the chamber 6. In operation, this pressure will be reduced by drawing off the gas through the connection 47. The line B-B represents the maximum level of the liquid in the tank 1, corresponding to the minimum level of the liquid in the chamber 6 and collar 2, indicated by the line C-C and lestablished by the water-seal vents. As the pressure of the gas falls, due to its consumption through the connection 47, there will be a reverse circulation of the water, cooler water from the outside tank entering the casing 6 and collar 2 through the openings 10 and 5. Evidently, if the gas in the chamber 6 is being drawn off and used as fast as generated, there will be no displacement of the water from the inner to the outer receptacle, or vice versa. Should, however, the valve 18 still be closed and the gas be used faster than it is being generated, the reverse circulation from the outer tank to the inner receptacle will occur. For each period or cycle of gas evolution. due to the delivery of a charge of carbide into the water, there will be a circulation of hot water from the interior receptacles to the outer tank; and, on withdrawal of gas and re- `duction'of pressure in the chamber 6, there will be a circulation in the op'posite direction of the cooler water from the outer tank to the limer During the receptacle. This circulation not only serves to prevent generation of gas in the tank 1, but also assists in insuring the presence of relatively cool water in the chamber 6 when a charge of carbide is dropped thereinto.

Reference has been made hereinbefore to the valve 18h. This valve serves as a safety cut-off against the feed of carbide under the following conditions:-

(a) Should the ring or link suspending the valve rod 19 break, or should the rod itself break, or should the diaphragm be ruptured, the bottom of the valve 18b will seat above the opening 17 and cut off the carbide supply;

(b) Should the generator be overturned when operating at full capacity, with the result that water will iiow out of the tank 1, the resultant escape of the gas will relieve the diaphragm 22 of pressure, and the spring 25 will operate to seat the valve 18 and cut oif any further supply of carbide from the receptacle 15.

(c) Should the carbide receptacle 15 be full when the generator is tipped over, the weight of the carbide in the receptacle, acting against the diaphragm 22, will counteract the pressure of the spring 25 sufficiently to seat the bottom valve 18.

The gas which is evolved within the generator is conducted through the water seal and coke bafe 35, for the purpose of removing therefrom any impurities that may be therein and for the drying of the gas, should such drying be necessary. Should a back pressure occur in the torch or burner and in the line connected to the coupling 47, oxygen will not be delivered to the generator, as an exit is provided therefor through the tube 45, the bottom of which will be unsealed before the water will uncover the bottom of the tube 44; and such back pressure can be vented through the opening 37a. Furthermore, should the pressure of gas in the chamberv 6 become excessive, such excess gas can escape through the pipe 45 and the vent 37a.

From the foregoing description, it is believed that it will be evident that I have produced an acetylene generator which is particularly safe and dependable in operation; which is foolproof; and which is extremely economical of production, while markedly ecient in operation.

Because of the provision at all times of a large volume of Water for the carbide charge as well as because of the manner of circulating the water, the temperature within the generator is ordinarily insucient to generate steam; hence the acetylene will be free from moisture and there will be no generation of gas from the lcarbide in its short passage from the bottom of the tube 13 to the water therebeneath. Furthermore, the tube 13 is itself kept dehydrated by the passage of the carbide therethrough.

Having thus described my invention, what I claim is:

1. An acetylene generator comprising in combination, a carbide receptacle having a discharge outlet at the bottom thereof, a valve controlling said outlet, a water receptacle below said carbide receptacle, and a feed tube for delivering smallsized carbide in a concentrated stream from the said outlet `to the Water receptacle, said tube being of such length and diameter as to cause the carbide to penetrate the surface of the water without floating thereon and to prevent access of moisture to said valve.

2. In an acetylene generator, the combination of an outer receptacle, a collar within the lower portion of said receptacle and secured to the inner wall thereof and having a seat extending inwardly from said Wall, a generating and gas receiving chamber having the lower end of its walls supported on said seat, a carbide receptacle arranged above the upper end of the said chamber and having gas-pressure controlled means for delivering charges of carbide into said chamber, the collar being provided with an opening therethrough adjacent the bottom thereof and the walls of the chamber being provided with an opening therethrough adjacent the bottom thereof and angularly spaced therefrom to provide a circuitous passage for water from the interior of the collar through the bottom of the chamber into the outer receptacle.

3. In an acetylene generator, the combination 0f an outer receptacle, a frusto-conical collar within the lower portion of said receptacle and secured to the inner wall thereof and having a seat extending inwardly from said wall, a frustoconical generating and gas-receiving chamber having its lower portion surrounding and spaced from the said collar and its lower end supported on said seat, a carbide receptacle having a hopper closing the upper end of the said chamber and provided with gas-pressure controlled means forl delivering charges of carbide into the water within said chamber and collar, the collar being provided with angularly spaced openings therethrough in the lower portion thereof above said seat and the walls of the chamber being provided with angularly spaced openings adjacent to the bottom thereof, the openings in the chamber being spaced angularly from the openings in the collar, whereby a circuitous route will be provided for the passage of water from the collar to the outer receptacle.

4. In an acetylene generator, the combination of an outer receptacle, a seat secured to the inner wall of said receptacle and extending inwardly from said wall, a generating and gas receiving chamber having its lower end supported on said seat and having openings adjacent such lower end, a carbide receptacle arranged above the upper end of the said chamber and having means for delivering carbide into said chamber, and locking means Within the inner wall of said receptacle and adjustable to engage the walls of said openings thereby to secure the lower end of said chamber to said seat and to position the said chamber within the outer receptacle.

5. In an acetylene generator, the combination of an outer receptacle, la seat secured to and extending inwardly from the inner wall of said receptacle, a generating and gas-receiving chamber having a bead at its lower end and resting on said seat, a carbide receptacle arranged above the upper end of the said chamber and provided with means for delivering carbide into the said chamber, and rods rotatably mounted on the inner wall of said receptacle and each having a projection at its lower end adapted to engage the top of said bead thereby to secure the chamber within the said receptacle.

LORN CAMPBELL, JR. 

